Colloid injection mill

ABSTRACT

A colloid mill having a milling zone defined by the area between the opposed surfaces of a stator and rotor disposed in milling relationship with each other, a first passageway for feeding a main product through the milling zone, and a secondary product passageway connected from a point exterior to said mill to the milling zone to provide a means for mixing a second product with the main product at a predetermined location within the milling zone while subjecting the second product to a lesser amount of shearing than the main product.

United States Patent OKeefe, deceased et al.

[54] COLLOID INJECTION MILL [72] inventors: David F. OKeeie, deceased, late of Long Island. N.Y.; by Keith Baker, executor, l 49 Kensington. Garden City,N.Y 11530 22 Filed: 0ct.1,l970

:1 AppliNo; 77,196

..B02c 7/175 Field of Search ..24 N14, 38, 244, 246, 247,

Behrens et al. ..24l/256 Fritzweiler et al. ..24 1/260 X Primary Examiner-Robert L. Spruill Attorney-Pennie, Edmonds, Morton, Taylor and Adams 5 7] ABSTRACT A colloid mill having a milling zone defined by the area between the opposed surfaces of a stator and rotor disposed in milling relationship with each other, a first passageway for feeding a main product through the milling zone, and a secondary product passageway connected from a point exterior to said mill to the milling zone to provide a means for mixing a second product with the main product at a predetermined lo- .cation within the milling zone while subjecting the second product to a lesser amount of shearing than the main product.

56 References C'ted 1 I l 5Claims,lDrawing Figure UNITED STATES PATENTS 1,993,762 3/1935 Tolman ..24l/245 II I 24 2 3| 25' l 32 l4 l5 2 9 l3 7 t 6 5; l5 5 *4 2s 1A e 33 I8 26 27 PATENTEDAPR 2 5 I972 ATTORNEYS COLLOID INJECTION MILL BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a colloid injection mill andin particular to a mill enabling selective mixing of products.

2. Description of the Prior Art Colloid mills have been developed and used to mix different products together to produce a single end product having a desired consistency. In general, these mills consist of a stator and rotor disposed within a milling chamber in millingrelationship with each other. By regulating such factors as the size and shape of the rotor, its rate of rotation and the timeperiod over which the products are sheared, the amount of shearing to which the products are subjected can be controlled to thereby attain an end product having the desired consistency.

The products to be mixed in the mill can be introduced through either a single passageway or through a plurality of passageways. In the latter case, the passageways join each other within the mill causing the products to be mixed together. These prior colloid mills have substantial disadvantages. Attempts to blend different products having different physical properties have not been altogether successful since such products usually require different amounts of milling. Also, the different products are normally required in different amounts and at different flow rates. Conventional mills are not specifically suited for handling two products under these variable conditions. Generally, they are limited with respect to the type of products that can be mixed therein at least to the extent that each of the products which is introduced into the mill is of such a nature as not to be destroyed by the full shearing action of the mill. In other words, each product must be independently capable of withstanding the full shearing action ofthe mill.

In addition to the above, disass'embly and cleaning of the conventional mill to clear any passageways or make repairs of any kind is time consuming and costly. Such cleaning and repairs can cause the mills to be inoperative for long periods of time.

SUMMARY OF THE INVENTION In accordance with the teachings of the present invention, the improved colloid mill includes a stator and cooperating rotor for milling two different products simultaneously and to different degrees. The first product is fed between the opposed surfaces of the rotor andstator along their entire axial length in the conventional manner. For introducing the second product, the rotor is provided with a passageway extending from a point exterior to the mill to a point communicating with the milling zone between the opposed surfaces of the stator and rotor. The point of communication with the milling zone is somewhere intermediate the axial ends of the rotor so that the second product is subjected to a lesser degree of milling than the first product. By using rotors having the exit of the passageway at different locations axially of its milling surface, different products may be mixed together and different milling operations may be performed.

The advantage of the colloid mill described herein is substantial. A product which might have been destroyed if placed in a colloid mill, can now be milled and mixed with another product without damage or destruction. In addition, the mill of the present invention is constructed to enable complete disassembly thereof with a minimumexpenditure of time and effort. This is of advantage when cleaning of the parts is necessary and when it is desired to replace the rotor with one of different operating characteristics.

BRIEF DESCRIPTION OF THE DRAWINGS The drawing is a longitudinal cross section view of the colloid injection mill embodying the features of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT The present invention resides in an improvement to conventional colloid mills such as disclosed in U. S. Pat. No. 3,224,689 issued Dec. 21, 1965.

The basic construction of the preferred embodiment of the mill of the present invention is the same as described in said patent; and accordingly, the description of such structure as contained in the present application is limited to that which is necessary for a complete understanding of the present inventron.

Referring to the drawing, the colloid mill, generally designated at 1, comprises a main housing structure 2 mounted upon a base 3 which can be secured firmly to some suitable foundation. A rotor shaft 4 extends through the main housing structure along the longitudinal axis of the mill and is supported for rotation therein by suitable bearing 5 and 6. One end 7 of the shaft extends beyond one axial end of the housing to a point external of the mill for connection to a suitable motor, not shown, by which it is driven. The other end 8 of the shaft extends into the milling section of the mill. A partition wall 9 and associated seal 10 surrounds the shaft 4 to isolate the milling section of the mill from the supporting and driving structure for the rotor shaft.

In the milling section, the main housing structure includes I an outer member 11 within which a stator 12 and cooperating rotor 13 are positioned. As shown, the stator 12 is provided with an internal conically shaped milling surface 14 which is in opposed milling relationship with the outer milling surface 15 of the rotor, the latter member being mounted on the rotor shaft 4 for rotation therewith. The opposed milling surfaces of the stator and rotor are appropriately grooved and the spacing therebetween may be varied to change the milling relationship by sliding the rotor shaft axially of the main housing structure. For this purpose, the rotor shaft is supported within a sleeve support 16 which is threadly connected to the housing structure as shown at 17.

The spacing between the stator and rotor defines a milling zone, the annular inlet 18 to which is located at the enlarged end of the rotor and the annular outlet 19 of which is located at the smaller end. The outlet 19 communicates with a product outlet chamber 20 which in turn communicates with a housing outlet 21 through which the milled product is dispensed from the mill. Disposed immediately adjacent the enlarged end of the rotor is a main product chamber 22. One wall ofthis chamber is defined by the enlarged end of the rotor with the outer wall thereof is defined by a housing sub-structure 23 which is removably attached to the main housing structure 22 by suitable bolts 24. The housing sub-structure 23 is provided with an opening 25 through which a main product may be fed into the mill. As will be seen from the drawing, the main product which is a high volume product, passes through the entire axial length of the milling zone during which it is subjected to the desired shearing action.

In some processing operations, as where different food products are to be milled and mixed together, one of the products may not be able to withstand a great amount of milling without destroying it or injuriously affecting its physical characteristics such as its consistency and taste. Also,

'there are instances where a portion of a formula or a recipe is not compatable when worked too hard. In accordance with the teachings of the present invention, such a product may be readily processed simultaneously with a less damageable product. This result is effected by providing a separate passageway for the secondary product which enters the milling zoneat a predetermined point where it is subjected to only a part of the shearing action to which the main product is subjected. Referring to the drawings, it is seen that the rotor blind end of the conduit 26, a plurality of radially extending conduits 27 are provided. These conduits 27 are aligned with similarly directed radial conduits 27 in the surrounding rotor which lead to points on the outer surface of the rotor that are in communication with the milling zone at some predetermined location intermediate the main product inlet 18 and the product outlet 19.

All ofthe radially extending conduits 27,27 are disposed in a common plane extending perpendicular to the longitudinal axis of the rotor and rotor shaft and are connected to the milling zone at points equally spaced from the product inlet 18. This assures that all of the secondary product will be subjected to the same amount of shearing as it is fed through the mill. As will be evident from the drawing, such shearing or milling of the secondary product will occur along the length of the opposed surfaces of the stator and rotor from the point of entry of the conduits 27' to the product outlet 19 at the small end of the rotor.

The secondary passageway passing though the rotor communicates with the exterior of the mill through the main product chamber 22. For this purpose, a rotor shaft extension 28 is threadly connected to the enlarged end ofthe rotor. This extension has an axial conduit 26' therein and extends out through the back of the main product chamber and into a secondary product chamber 29. A bearing seal generally designated at 30 is positioned between the extension and the opposed housing substructure 23 for isolating the main and secondary product chambers from each other. With this bearing seal construction, the shaft extension is also free to rotate relative to the housing structure.

The secondary product chamber 29 is defined by the housing sub-structure 31 which is removably attached to the substructure 23 by suitable bolts 32. An opening 33 in the substructure 31 leads to the exterior of the mill and through it the secondary product is introduced into the product chamber 29. The injection of the secondary product into the mill through the opening 33 is controlled by a low volume positive pump, not shown.

In addition to enabling a mixture of different products within the mill while subjecting one of them to less shearing than the other, the present invention also provides a mill which can be simply dismantled to replace the rotor with one having radial conduits communicating with the exterior thereof at different locations along its axial length. Accordingly, different secondary products requiring different degrees ofmilling may be readily processed in the mill.

To remove the rotor from the mill, the bolts 32 are first removed to permit removal of the sub-structure 31. The bearing seal 30 is then loosened and removed. Next the sub-structure 23 is removed by removing bolts 24. Thereafter, the rotor shaft extension 28 is unscrewed from the rotor shaft 4 and the rotor 13 can then be removed by a rotor puller.

Although the preferred embodiment of the present invention has been described above, it will be apparent to one skilled in the art that various changes may be made thereto without departing from the scope of the invention as set forth in the following claims.

What is claimed is:

1. In a colloid mill having a housing, a rotor shaft supported within said housing, a rotor mounted on said shaft for rotation therewith, said rotor having a conically shaped outer surface defining one wall of a milling zone, a stator positioned in concentric, milling relationship about said rotor, the inner surface of said stator being conical and defining the other wall of said milling zone, said milling zone extending a predetermined distance along the axial length of the rotor, a main product inlet at one end of said milling zone adjacent the enlarged end of said rotor, and a product outlet at the other end of said milling zone, the improvement comprising:

a. a secondary product passageway leading from a point exterior to said mill to a point in communication with said milling zone, said passageway including:

l. A main conduit extending axially through said rotor from the enlarged end adjacent said main product inlet to a point spaced from its other end, and

2. at least one radially extending conduit leading from said main conduit to a point on the outer surface of said rotor and in communication with said milling zone intermediate said main product inlet and said product outlet.

In a colloid mill as defined in claim I further including:

a main product chamber disposed within said housing in communication with said main product inlet and with one wall being defined by the enlarged end of said rotor;

b. a first opening in said housing connecting the exterior of the mill to said main product chamber and through which said main product is introduced into said mill;

. a secondary product chamber disposed axially outwardly ofsaid main product chamber;

d. a rotor shaft extension connected to the enlarged end of said rotor and extending through said main product chamber and into said secondary product chamber, said rotor shaft extension having a conduit extending axially therethrough and connecting the main conduit of said rotor to said secondary product chamber;

. sealing means for sealing said main product chamber from said secondary product chamber; and

. a second opening in said housing connecting the exterior of said mill to said secondary product chamber and through which said secondary product is introduced into said mill.

3. In a colloid mill as defined in claim 2 wherein said hous ing includes:

a. a main structure for supporting said rotor shaft and stator,

b. a first sub-structure defining the outer wall of said main product chamber; and

c. a second sub-structure defining a wall portion of said secondary product chamber; and

d. means for removably connecting said sub-structures to said main structure to provide access to said rotor for replacement thereof.

4. In a colloid mill as defined in claim 2 wherein said rotor includes a. a plurality of radially extending conduits connected to the outer surface of said rotor at points equally spaced from the product inlet to said milling zone.

5. In a colloid mill as defined in claim 4 wherein:

a. said radially extending conduits are disposed in a common plane extending perpendicular to the longitudinal axis ofsaid rotor.

Q2 33 UMTED STATES PATENT OFFICE CERTEFICATE OF CORRECllON Patent No. ,658,266 April 25 1972 Invcntor(s) David F. O! Keefe deceased; Keith Baker, executor It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Page 1, Column 1, after the name and address of the executor insert the following:

Garden City Park, New York."

Signed and sealed this ZLrth day of October 1972.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents "Assignee: Chemicolloid Laboratories, Inc. 

1. In a colloid mill having a housing, a rotor shaft supported within said housing, a rotor mounted on said shaft for rotation therewith, said rotor having a conically shaped outer surface defining one wall of a milling zone, a stator positioned in concentric, milling relationship about said rotor, the inner surface of said stator being conical and defining the other wall of said milling zone, said milling zone extending a predetermined distance along the axial length of the rotor, a main product inlet at one end of said milling zone adjacent the enlarged end of said rotor, and a product outlet at the other end of said milling zone, the improvement comprising: a. a secondary product passageway leading from a point exterior to said mill to a point in communication with said milling zone, said passageway including:
 1. A main conduit extending axially through said rotor from the enlarged end adjacent said main product inlet to a point spaced from its other end, and
 2. at least one radially extending conduit leading from said main conduit to a point on the outer surface of said rotor and in communication with said milling zone intermediate said main product inlet and said product outlet.
 2. at least one radially extending conduit leading from said main conduit to a point on the outer surface of said rotor and in communication with said milling zone intermediate said main product inlet and said product outlet.
 2. In a colloid mill as defined in claim 1 further including: a. a main product chamber disposed within said housing in communication with said main product inlet and with one wall being defined by the enlarged end of said rotor; b. a first opening in said housing connecting the exterior of the mill to said main product chamber and through which said main product is introduced into said mill; c. a secondary product chamber disposed axially outwardly of said main product chamber; d. a rotor shaft extension connected to the enlarged end of said rotor and extending through said main product chamber and into said secondary product chamber, said rotor shaft extension having a conduit extending axially therethrough and connecting the main conduit of said rotor to said secondary product chamber; e. sealing means for sealing said main product chamber from said secondary product chamber; and f. a second opening in said housing connecting the exterior of said mill to said secondary product chamber and through which said secondary product is introduced into said mill.
 3. In a colloid mill as defined in claim 2 wherein said housing includes: a. a main structure for supporting said rotor shaft and stator, b. a first sub-structure defining the outer wall of said main product chamber; and c. a second sub-structure defining a wall portion of said secondary product chamber; and d. means for removably connecting said sub-structures to said main structure to provide access to said rotor for replacement thereof.
 4. In a colloid mill as defined in claim 2 wherein said rotor includes a. a plurality of radially extending conduits connected to the outer surface of said rotor at points equally spaced from the product inlet to said milling zone.
 5. In a colloid mill as defined in claim 4 wherein: a. said radially extending conduits are disposed in a common plane extending perpendicular to the longitudinal axis of said rotor. 